Civil Engineering Reference
In-Depth Information
(about 60-90 MPa) can be produced with 30-50% FA replacement (Dinakar
et al., 2008). sCC containing 40-60% FA and 0.35-0.45 water to binder
ratio provides sufficient compressive strength, ranging from 25 to 50 MPa
(Bouzoubaa and lachemi, 2001). The long-term strength of sCC containing
60% high-volume FA is around 40 MPa (Khatib, 2008). This implies that
high-volume FA can be used to produce sCC with adequate strength.
sCC containing more than 50% FA replacement produces compressive
strength of 20-30 MPa at 3-7 days (Kumar et al., 2004). The early-age
strength value of sCC containing 50% FA is low due to the slower reactivity
of FA. This can be improved by using a ternary blend of 25% FA and 25%
GGBFs; in this case the 28- and 91-day compressive strength values exceed
the results from the reference mixtures (nehdi et al., 2004). similarly, the
compressive strength decreases as the FA replacement ratio increases (Pathak
and siddique, 2012). in contrast to FA, sCC with GGBFs provides comparable
strength values (Gesoğlu and Özbay, 2007; Güneyisi et al., 2011). The 28-
day compressive strength of sCC incorporating 30% FA and 30% GGBFs
with a suitable superplasticiser becomes around 70 MPa, and the resulting
concrete mix provides adequate fluidity, cohesiveness and water-retaining
properties (Fang
et al., 1999).
As shown in Fig. 9.2, the compressive strength of sCC with binary blends
TBC = 550 kg/m
3
(Dinakar et al., 2008)
TBC = 550 kg/m
3
, w/b = 0.32 (Gesog
˘
lu & Özbay, 2007)
TBC = 400 kg/m
3
, w/b = 0.35 (Bouzoubaa & Lachemi, 2001)
TBC = 400 kg/m
3
, w/b = 0.40 (Bouzoubaa & Lachemi, 2001)
TBC = 400 kg/m
3
, w/b = 0.45 (Bouzoubaa & Lachemi, 2001)
TBC = 500 kg/m
3
, w/b = 0.36 (Khatib, 2008)
70
60
50
40
30
20
10
30
40
50
60
70
80
90
FA replacement ratio (%)
9.2
The 28-day compressive strength variation in terms of FA
replacement ratio.
